A Novel De Novo Missense Variant in Netrin-1 (NTN1) Associated With Chorioretinal Coloboma, Sensorineural Hearing Loss and Polydactyly.

Microphthalmia, anophthalmia and coloboma (MAC) comprise a highly heterogeneous spectrum of congenital ocular malformations with an estimated incidence of 1 in 5000 to 1 in 30 000 live births. Although there is likely to be a genetic component in the majority of cases, many remain without a molecular diagnosis. Netrin-1 was previously identified as a mediator of optic fissure closure from transcriptome analyses of chick and zebrafish and was shown to cause ocular coloboma when knocked out in both mouse and zebrafish.